import java.util.Scanner;

public class demo03 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入本次购物的价格：");
        double a = scanner.nextDouble();
        System.out.println("亲，包邮吗？(请输入yes or no)");
        String b = scanner.next();
        if (b.equals("yes")){
            System.out.println(a);
        }else {
            System.out.println(a+20);
        }
    }
}
